There's no system that will perfectly allow people to both find value and meaning in their world AND also promote totally free action of others.
Thus we live in a contemporary world of non-religious people seeking out value (look at the current obsession in Silicon Valley with Stoicism, mindfulness, pyschadelics, etc). But Silicon Valley also tells their people that they can't use those methods to find an actual belief system of values. It's like, definitely always look for meaning and value in the universe, we like that. But, don't find it and a be bold about it.
Catholics are against birth control because we're for a world in which human life is nourished, valued, and lifted up within the family. Not that it's seen as a problem to be dealt with. A knock on impact of that mentality is the sex becomes seen as a sacred act of deep value to humanity, an act with profound power and responsibility.
Almost no Catholics suggest that we legally outlaw birth control. We recognize that fundamentally free agency should be left to moral agents (unless it cause a direct moral hazard to others like abortion, theft, dishonesty, etc). But why would we change our view on reproduction and the family? Moreso, birth control doesn't even do that great of a job at slower birth rates in developing nations.